1. Field of the Invention
The present invention relates to an image formation apparatus, an image formation system, and an output control method. In particular, the present invention relates to an image formation apparatus to which a post processing apparatus is connected; an image formation system including the image formation apparatus and the post processing apparatus; and an output control method in the image formation apparatus.
2. Description of the Related Art
In recent years, in order to deal with various printing styles, image formation systems for continuously performing processes from printing to a post process such as bookbinding have been pervasive.
For such an image formation system, Japanese Laid-Open Patent Publication No. 2008-077420 (hereinafter, referred to as “Patent Document 1”) discloses an image formation system including: a power supply line for supplying power, which has been supplied to a post processing apparatus from an apparatus of a previous stage, to an apparatus of a subsequent stage; and boosting means for increasing voltage of the power thus supplied. The post processing apparatus includes: voltage monitoring means for monitoring an output voltage level in the power supply line thus adapted to supply the power to the apparatus of the subsequent stage; and boosting control means for causing the boosting means to increase the voltage when a result of the monitoring by the voltage monitoring means is smaller than a predetermined output voltage level.
In Patent Document 1, such a configuration prevents the post processing apparatus from being influenced by voltage drop resulting from impedance in the power supply line.
Meanwhile, Japanese Laid-Open Patent Publication No. 2005-345663 (hereinafter, referred to as “Patent Document 2”) discloses a power saving method for stopping a part of driving units of an image formation apparatus in synchronism with a period during which power consumption of a sheet post processing unit is at maximum.
Meanwhile, Japanese Laid-Open Patent Publication No. 2006-007581 (hereinafter, referred to as “Patent Document 3”) discloses an image formation apparatus having a power source for driving an image controller or a CPU (Central Processing Unit) using a DC/DC converter of separate excitation type. When powered on, the DC/DC converter included in the image formation apparatus detects an option for supply of sheets and a status regarding incorporation of an external device such as an image scanner, estimates a load current, and drives it at an optimum PWM frequency. In this way, power consumption is reduced in the image formation apparatus.